Here's what you do-
Kill the girl, take the body with you to killington. They call it killington for a reason. After a good solid 3 days of sex after skiing, dispose the now rotting body. Sometimes it takes more time for it to rot, depending on how many preservatives she ate on a regular basis. Get her to eat lots of microwave dinners before you kill her. Remember, after 4 days you can catch a really nasty disease, so be careful: a human body is not milk, you cant drink it after its expiry date.